1. Field
The present invention relates to heterocyclic sulfonamides, methods for their manufacture, and their use as medicaments, especially for treating chronic heart failure.
2. Description
Sulfonamides are known inhibitors of endothelin receptors. See, for example, EP 0 713 875. There is a need for endothelin receptor inhibitors that have high antagonistic potency and achieve high plasma levels following oral administration.
The subject invention provides compounds of formula: 
wherein
R1 is pyridyl, pyridyl substituted with lower alkyl, pyridyl substituted with lower alkenyl, thiazolyl, thiazolyl substituted with lower alkyl, or thiazolyl substituted with lower alkenyl;
and pharmaceutically usable salts of such compounds.